Cases for electrical components such as outlet strips or panels, certain switches and certain motor controls are typically stamped from sheet metal in the form of a base and a cover which together define a box-like space for receiving the electrical component. Either the base or the cover or both typically include one or more integral ears or tabs, usually lying in the plane of the base, having slots or holes so that the case can be permanently mounted to a mounting surface by fasteners such as screws passing through the slots or holes.
Some environments require that the case of an electrical component be incapable of being permanently mounted to a mounting surface. In this sense permanently mounted means that one or more of the screws or other fasteners which penetrates into the mounting surface must be removed from the surface before the case can be released. In these environments it is permissible and desirable for the case to be non-permanently mounted in the sense that the case can be released from its fasteners or from mounting brackets without first removing the fasteners or brackets from the mounting surface. Inasmuch as such cases may be otherwise identical with the conventional permanently mountable cases there is a need for a modification to a case and/or to the method of manufacture of a case which will permit the manufacture of a single basic form of case which can be easily adapted to either a permanently mountable or non-permanently mountable form. For example, in the manufacture of a conventional permanently mountable case it is conventional to punch out the mounting slots or mounting holes at some point in the production line, usually simultaneously with a pressing operation. It would be inconvenient and costly to change the production line to omit the slots or holes in order to produce a batch of non-permanently mountable cases. Similarly once a production line has been set up to produce non-permanently mountable cases it is not convenient to modify it to produce a batch of conventional cases.
In accordance with one of the principles of the present invention a case for an electrical component is formed in a conventional manner so as to have perforated or slotted mounting ears or tabs and is then provided with permanently affixed mounting means capable of effecting temporary mounting, these means overlying the mounting holes or mounting slots. In this way a single production line may be employed to produce the basic case for either permanent or temporary mounting. The invention also includes the non-permanently mountable case made in this manner.
The invention also contemplates the manufacture of a non-permanently mountable case having no mounting holes or mounting slots but including temporary mounting means and ears or tabs which can be punched to produce permanent mounting holes or slots.